Snellen Chart

Unit 4 Snellen Chart
Medical equipment, Operator Care and Maintenance. Series of 10 Units, designed for use by health practitioners in rural and remote areas in countries in development. Enquiries: Bastiaan Remmelzwaal, bastiaan@remm.net

Category:

Education

Tags:

• snellen
• chart
• medical
• equipment
• device
• operator
• care
• maintenance
• hospital
• clinic
• health
• HTM
• Bastiaan

[blr99]

You need patients and patience too! :-)

[otissumnerbrown]

The bottom line. The goal is to show that the eye resolves to 1 minute-of-angle at distance. At 20/40, that is 2 minutes-of-angle. The 20/20 letters subtend 5 minutes of arc.

[otissumnerbrown]

@maryjanemars That depends on the State requirements. They run from 20/60 for Georgia, and 20/50 for the State of Texas. Almost all the rest require 20/40 with 1) Both eyes open or, 2) With the better eye. The 20/40 letter is 3/4 inch high to be read at 20 feet. Metric, 1.8 cm at 6 meters.

[lovesucks38]

nice

[zaxlor]

@ 3:49 Eye eye captain! Loving your pink eye patch!

[biggsterboy]

@Commando303X  The lively musical punctuations help get me through the dull narrated parts. If you get stuck at 3:46 due to boredom from the dull narration, try your best to hang in there: you will be rewarded with a lively musical punctuation at 4:15, and this will likely get you through to the end.

[Commando303X]

Dull narration punctuated with lively music.

Also, I can't get past 3:46...

[bozzie111]

This video is boring and tooooooooo slow 

[maryjanemars]

What line do they ask you to read when your taking the Drivers license eye test??

[otissumnerbrown]

Snellen 20/20, means the letter is 3/8 inch high. for 20/40 the letter is 3/4 inch. For metric, the letter is 0.9 cm fo 6/6 vision and 1.8 cm for 6/12.